Test ID VMA Vanillylmandelic Acid, 24 Hour, Urine
Ordering Guidance
In the past, this test has been used to screen for pheochromocytoma. However, vanillylmandelic acid (VMA) is not the analyte of choice to rule out a diagnosis of pheochromocytoma. Recommended tests for that purpose include:
-PMET / Metanephrines, Fractionated, Free, Plasma
-METAF / Metanephrines, Fractionated, 24 Hour, Urine
-CATU / Catecholamine Fractionation, Free, 24 Hour, Urine
Necessary Information
1. Patients age is required.
2. Collection duration and urine volume (in milliliters) are required.
3. All patients receiving L-dopa should be identified to the laboratory when this test is ordered.
4. Bactrim may interfere with detection of the analyte. All patients taking Bactrim should be identified to the laboratory when this test is ordered.
Specimen Required
Patient Preparation: Administration of L-dopa may falsely-increase vanillylmandelic acid results; it should be discontinued 24 hours prior to and during specimen collection.
Supplies: Urine Tubes, 10 mL (T068)
Specimen Volume: 5 mL
Collection Instructions:
1. Collect a 24-hour urine specimen.
2. Add 25 mL of 50% acetic acid as preservative at the start of collection. If specimen is refrigerated during collection, preservative may be added up to 12 hours after collection. Use 15 mL of 50% acetic acid for children <5 years old. This preservative is intended to achieve a pH of between approximately 1 and 5. If necessary, adjust urine pH to a level between 1 and 5 by adding 50% acetic acid or hydrochloric acid dropwise and checking the pH..
Additional Information: For multiple collections see Urine Preservatives-Collection and Transportation for 24-Hour Urine Specimens.
Forms
If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.
Secondary ID
9454Useful For
Screening children for catecholamine-secreting tumors using a 24-hour urine collection when requesting testing for vanillylmandelic acidonly
Supporting a diagnosis of neuroblastoma
Monitoring patients with a treated neuroblastoma
Special Instructions
Method Name
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
Reporting Name
Vanillylmandelic Acid, 24 Hr, USpecimen Type
UrineSpecimen Minimum Volume
2 mL
Specimen Stability Information
Specimen Type | Temperature | Time | |
---|---|---|---|
Urine | Refrigerated (preferred) | 28 days | |
Frozen | 180 days |
Clinical Information
Vanillylmandelic acid (VMA) and other catecholamine metabolites (homovanillic acid [HVA] and dopamine) are typically elevated in patients with catecholamine-secreting tumors (eg, neuroblastoma, pheochromocytoma, and other neural crest tumors). VMA and HVA levels may also be useful in monitoring patients who have been treated as a result of one of the above-mentioned tumors.
Reference Values
<1 year: <25.0 mg/g creatinine
1 year: <22.5 mg/g creatinine
2-4 years: <16.0 mg/g creatinine
5-9 years: <12.0 mg/g creatinine
10-14 years: <8.0 mg/g creatinine
≥15 years (adults): <8.0 mg/24 hours
Cautions
Values are more commonly elevated during a hypertensive episode.
Values may be normal in some individuals with pheochromocytoma.
All patients taking Bactrim should be identified to the laboratory when vanillylmandelic acid and homovanillic acid tests are ordered due to potential interference.
Day(s) Performed
Monday through Friday
Report Available
3 to 5 daysPerforming Laboratory

Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
84585